Question

I’m having a problem with a PHP website running on IIS 7 on Windows Server 2008.

There is one line of code calling mkdir which is erroring and the error log reads:

“… permission denied …”

I have ruled out anything to do with folder permissions (I have tried multiple groups: Everyone, Users, IUSR, Network Service etc. with no luck).

I need to know how mkdir works, does it check the read-only attribute of the parent folder?

If so, then this could be the root of the problem as all folders in Windows Server 2008 are marked as “Read Only” and the checkbox is greyed-out – Microsoft say it is “by design” but I think it is really “bad design”.

Please help.

P.S. The line of code which errors can be found here https://github.com/LimeSurvey/LimeSurvey/blob/070d255ba381d7abcd231d7c9e0c7d11f5578c97/admin/templates.php#L1182 it is line 1182.

SOLUTION:

• It was a permissions issue after all!
• We were applying permissions to the wrong folder (smacks hand to forehead)
• There are two “Templates” folders: /Templates and /Uploads/Templates
• /Template is for default templates whereas /Uploads/Templates is for user-created ones
• We gave the “Users” group r/w/execute/modify permissions to /Uploads/Templates folder
• Whereas previously we were applying permissions to /Templates
• To debug this I used echo to output the $target value

LESSONS LEARNT:

• Always read the error message – it said “permission denied” and I didn’t believe it
• Don’t assume the obvious to be true – /Templates wasn’t the right folder
• If the code is erroring then debug the code and don’t try to guess the problem
• Debug the code using simple techniques such as outputting variable values – e.g. echo
• Listen to the majority – most people here were right in saying IT IS A PERMISSIONS ISSUE!
• Most errors have a simple fix – don’t go looking for something complex

Bounty awarded to @BOMEz because of the useful quote from mkdir() documentation which indicated that I should double-think the permissions. @BOMEz also provided a tailored answer and interacted with me via comments which helped.

Answer 1

• As a test (preferably in a development environment) give the IIS user full access to the parent folder. If this makes it work, slowly start taking away privileges to see which ones you need.

• Try changing:

  if(mkdir($target,0777))

to:

if(mkdir($target))

Windows ignores the mode option. Might be some weird bug causing it to fail.

Additionally for your $target variable could you try forcing it to link to the full Windows path? Such as C:\Program Files\ IIS\...

I’ve ran into situations with windows before where access was denied attempting to use a relative path, but the full path works just fine.

EDIT:
Looking at the comments on the documentation for mkdir() one commenter mentions that you might also need to add execute permissions to the user:

If you’re getting a Permission Denied error, but are certain the
permissions and ownership where you are trying to create the directory
are correct, check again:

The location where you are trying to create the directory in must have
the Execute permission for the owner trying to create it, regardless
of if the folder is Readable, or Writable.

This may be obvious to some, but was not to me at first. Hopefully
this will save you the trouble I went through.